Transfer of fruits in shipping containers necessitates a certain composition of a gas medium inside the container. That composition should change depending upon the type of fruits, the degree of their ripeness, and the technology for preparation of these fruits for sale.
There are known inventions related to the systems for controlling gas media in shipping containers.
U.S. Pat. No. 5,333,394, “Controlled atmosphere container system for perishable products”, Herdeman, et al., issued Aug. 2, 1994, includes a description of a system that is connected to the inlet connecting pipe of the container, allowing control of the gas medium inside it. The system includes the central source of the gas medium, which is connected through pipes and channels to a number of containers into which the required gas medium is pumped.
U.S. Pat. No. 6,092,430, “Oxygen/carbon dioxide sensor and controller for a refrigerated controlled atmosphere shipping container”, Liston, et al, issued Jul. 25, 2000, includes a description of a device for controlling a gas medium in a container intended for shipping of perishable products, in particular, fruits. The device includes an inlet connecting pipe, intended for the intake of atmospheric air, which is first cleaned from dust and moisture. Then, using a compressor, the air is passed through a nitrogen-permeable membrane filter. The separated nitrogen is further directed inside the container. The device is also equipped with a vessel with carbon dioxide, and with a system for feeding carbon dioxide into the container. The container is equipped with a system for controlling carbon dioxide and oxygen content in the gas medium, and for pumping nitrogen into the container.
U.S. Pat. No. 6,615,908, “Method of transporting or storing perishable product”, Bosher, et al., issued Sep. 9, 2003, includes a description of a device for controlling the gas medium inside a container. The device includes a diffusion membrane through which atmospheric air is pulled into the container. The membrane conducts carbon dioxide, and does not conduct oxygen. The gas medium in the container is modified by releasing parts of it from the container through a release valve, and by substituting it for gas that has passed through the above-mentioned membrane.
Existing devices for regulation of gas media in containers involve complicated equipment. They also require significant energy consumption for passing atmospheric air through filters, and for generating excessive pressure inside the container necessary to release the gas medium being substituted through the outlet valves.